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	A method for detecting coalbed methane gas storage structure in coal goaf - A case in Qinshui coal field in Shanxi province 期刊论文 OAI收割 CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION, 2022, 卷号: 65, 期号: 11, 页码: 4495-4503 作者: Tian ZhongBin; Ma YuLong; Li Xiu; Ji YanJu; Li DongSheng \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2023/03/31 Mined-out area Coalbed methane gas storage structure Semi-airborne transient electromagnetic method Quickly Indirectly
	The research on adaptive measurement of angular acceleration for photoelectric servo turntable (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China 作者: Guo J.; Chen J.; Guo J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 The paper proposes a new measurement method of angular acceleration for photoelectric servo turntable. Piezoelectric angular acceleration sensor is used to measure angular acceleration directly Adaptive FIR filter based on LMS algorithm is established on DSP by which angular acceleration signal can be filtered and corrected errors adaptively then angular acceleration signals can be measured adaptively. This method avoids measurement errors and calculation noise by computing angular acceleration indirectly thus improving measurement precision and making measurement results better than traditional methods. The gotten angular acceleration can be sent to servo control mechanism as feed forward control signals to improve control effects of servo turntable significantly. 2011 IEEE.
	A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Sun Y.; Sun Y.; Wan Q.-H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid according to the difficulties of the detection of the magnetic fluid established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid which followed the movement of the magnetic fluid and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA whose width and depth were designed by the user as required. Then the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus whose transmission rate can reach 480Mb/s in theory. Finally the distribution of the laser speckle on the magnetic fluid was messy and random which carried certain information about the surface of the magnetic fluid based on the theories of the statistic correlation and the subdivision of images analysing and processing the laser speckle interferometric images indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court non-contact non-invasive high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.
	Research on 10.6 m laser beam monitoring in CO2 laser processing system (EI CONFERENCE) 会议论文 OAI收割 Infrared Materials, Devices, and Applications, November 12, 2007 - November 15, 2007, Beijing, China 作者: Gao Y.; Shao S. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 It is a key point of CO2 laser beam monitoring in the CO 2 laser processing system to achieve alignment between CO2 laser and PL (pointing and launching) system. By monitoring the angle offset of CO2 laser beam the compensation can be gotten witch is given to fast-steering mirror to rectify the direction of laser beam. But the normal photoelectric detector can not get the laser signal because of CO2 laser's high energy and long wavelength. Its wavelength is 10.6m and its power can reach kW level. Consequently it is difficult to detect the high-energy 10.6m laser beam directly. So we monitored the output mirror of laser resonator superseded the laser beam indirectly. The laser beam monitoring system could be designed based on CCD laser auto-collimation angular measurement principle and image processing method. In this paper application of CCD laser auto-collimation angular measurement principle and image processing method for CO2 laser beam monitoring system is introduced particularly After design fabrication and alignment the monitoring system can be used for experimental study that including angular measurement accuracy and angle offset measurement of CO2 laser beam. Angle offset range and angle variation rule of CO2 laser beam is also can be acquired for further research.